Functions

I18N

translate

Get a translation by its key. Additional arguments are interpolated as dynamic values in the string.

Returns: string

Param	Type	Description
key	string	Translation key
…values	string	Dynamic values to interpolate

{{ translate('hello_world') }}

{{ translate('hello_world', 'dynamic', 'strings') }}

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i18n_all

Get all available languages.

Returns: array of language objects

{{ i18n_all() }}

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i18n_current

Get the current language name.

Returns: string

{{ i18n_current() }}

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i18n_current_code

Get the current language locale code (e.g. en_US).

Returns: string

{{ i18n_current_code() }}

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i18n_other

Get all languages except the current one.

Returns: array of language objects

{{ i18n_other() }}

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i18n_is

Check whether the given locale code is the active language.

Returns: bool

Param	Type	Description
code	string	Locale code to check (e.g. nl_NL)

{{ i18n_is('nl_NL') }}

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i18n_format_code

Formats a locale code, normalizing region variants (e.g. en_GB → en_EN).

Returns: string

Param	Type	Description
code	string	Locale code to format (e.g. nl_NL)

{{ i18n_format_code('nl_NL') }}

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FacetWP

facet_wp

Render a facet created with the FacetWP plugin.

Returns: void (outputs HTML directly)

Param	Type	Description
name	string	Facet machine name as defined in FacetWP

{{ facet_wp('facet_name') }}

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Nonce

nonce_ajax

Generate a nonce value for an AJAX action. Pass the result as a data-nonce attribute on your trigger element.

Returns: string

Param	Type	Description
action	string	AJAX action route in dot notation (e.g. ajax.actions.my-action)

{{ nonce_ajax('ajax.actions.my-action') }}

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Query Monitor

qm_start

Start a Query Monitor profiling session.

Returns: void

Param	Type	Description
name	string	Unique identifier for this session

{{ qm_start('unique_name') }}

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qm_stop

Stop a previously started profiling session.

Returns: void

Param	Type	Description
name	string	Must match the name passed to qm_start

{{ qm_stop('same_name_as_qm_start') }}

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qm_lap

Record a lap time on a running profiling session without stopping it.

Returns: void

Param	Type	Description
name	string	Must match the name passed to qm_start

{{ qm_lap('same_name_as_qm_start') }}

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CSS

clsx

Build a space-separated class string from mixed inputs — strings, conditional expressions, arrays, and objects. Equivalent to the clsx utility in React.

Returns: string

{{ clsx('btn', isPrimary and 'btn-primary', ['btn-large'], { 'active': isActive }) }}
outputs "btn btn-primary btn-large active"

Supported input types

Type	Example
String	'btn'
Conditional (use and)	isActive and 'active'
Array	['btn', 'btn-large']
Associative array	{ 'active': isActive }

Falsy values (false, null, empty string) are ignored. Nested arrays are flattened.

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HTML

html_attribute

Render an HTML attribute string. If value is empty the attribute is omitted entirely.

Returns: string

Param	Type	Description
name	string	Attribute name
value	string	Attribute value — omitted if empty
condition	bool	Optional. When false, attribute is not rendered regardless of value

{{ html_attribute('data-src', image.src) }}
outputs data-src="https://somesite/image.jpg"

{{ html_attribute('data-src', image.src, true) }}
outputs data-src="https://somesite/image.jpg"

{{ html_attribute('data-src', image.src, false) }}
outputs ""

Page templates

page_template_permalink

Get the permalink of the first published page using a page template, e.g. to link to an overview page without hardcoding its URL.

Returns: string|null, null when no published page uses the template

Param	Type	Description
template	string	Template name (contact) or path (templates/contact.php)

{% set contactUrl = page_template_permalink('contact') %}

{% if contactUrl %}
    <a href="{{ contactUrl }}">Contact</a>
{% endif %}

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Debug

template_error

Report a misused partial, such as a required variable that is missing or invalid. With WP_DEBUG on it throws a Twig error that names the template and line. Without it, the message is logged to the PHP error log and the page keeps rendering.

Use it instead of silently falling back to a default, so mistakes surface during development.

Returns: nothing

Param	Type	Description
message	string	What is wrong

{% if image is not defined %}
    {{ template_error('partials/image.twig: `image` is required') }}
{% endif %}